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%I #15 May 27 2019 01:55:46
%S 1,4,3,8,5,12,7,16,9,20,11,24,13,28,30,32,17,36,19,40,42,44,23,72,25,
%T 52,27,56,29,60,31,64,33,68,35,108,37,76,39,80,41,84,43,88,90,92,47,
%U 144,49,100,51,104,53,108,55,112,57,116,59,180,61,124,126,128,65,132,67,136,69
%N Closest number to sigma(n) = A000203(n) which is divisible by n.
%C In the case of a tie, we round up. - _Robert Israel_, May 26 2019
%H Robert Israel, <a href="/A082895/b082895.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = n*floor((floor(n/2)+sigma(n))/n).
%e n=100: sigma[100]=217 is between 100=1.100 and 200=2.100
%e 200 is closer to 217, so a[100]=200;
%p f:= proc(n) uses numtheory; n*floor((floor(n/2)+sigma(n))/n) end proc:
%p map(f, [$1..100]); # _Robert Israel_, May 26 2019
%t Table[n*Floor[(Floor[n/2]+DivisorSigma[1, n])/n], {n, 1, 100}]
%o (PARI) a(n)=sigma(n)\/n*n \\ _Charles R Greathouse IV_, Feb 15 2013
%Y Cf. A082893-A082900, A000203.
%K nonn,look
%O 1,2
%A _Labos Elemer_, Apr 22 2003
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